This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Development of isoform selective NOS inhibitors continues to be the central focus of this proposal. Based on structural information gathered during the two previous proposal periods, a new generation of nNOS selective inhibitors were designed de novo (ref. 1). The new compounds were screened through in vitro inhibitory assays. Those shown to have good potency and selectivity were then used for structural studies. The best inhibitors were also found to protect against cerebral palsy induced by brain hypoxia in pre-clinical animal tests (ref.2). The enzyme-inhibitor complex structures are critical for further modification and improvement of new inhibitors.